The surname Stewart has large concentrations in the United States (mainly in the Deep South, and the other southern states), United Kingdom (mainly in Scotland, Northern Ireland, North East England, South West England, Cumbria, Lancashire, and Yorkshire), Canada, Jamaica, New Zealand, Australia and elsewhere that has large Scottish or Ulster Scots diaspora.
The progenitor of the Stewart family was Alan fitz Flaad, a Breton knight who settled in England after the Norman Conquest.
Mary, Queen of Scots formalised the use of the spelling Stuart, while resident in France, in order to preserve the correct pronunciation.
The Stewart dynasty ruled Scotland, England and Wales (with an interruption during Cromwell's Commonwealth after the English Civil War) until 1714, when Queen Anne died and the British Crown passed to the German Electors of Hanover.
In addition to the Royal House of Stuart, various branches of the Stewart family became Scottish peers, at various times holding the Marquisate of Bute, the earldoms of Atholl, Mar, Moray, Angus, Galloway, as well as several Lordships of Parliament.